Characteristics of Chemical Reactions

In a chemical process, atoms that make up a substance are regrouped into different __________ to form new substances with different properties.

• molecules

• color

• precipitate

• light

• gas

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

A ___________ increase or decrease and the production of light are both signs that a chemical reaction may have occurred.

• light

• temperature

• odor

• precipitate

• molecule

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

A __________ is a solid substance that forms and separates from a solution and may indicate that a chemical reaction has occurred.

• light

• color

• gas

• precipitate

• molecule

Tags

NGSS.MS-PS1-2

An unexpected change in ____________ is a sign that a chemical reaction may have occurred.

• molecule

• color

• light

• precipitate

Tags

NGSS.MS-PS1-2

Substances giving off a smell (____________) while being combined is also an indicator of a chemical reaction.

• light

• odor

• molecule

• precipitate

Tags

NGSS.MS-PS1-2

Calcium Chloride was mixed with water and WHAT OTHER REACTANT to have a product that increases in temperature and produces a gas.

• Baking Soda

• Vinegar

• Cornstarch

• Phenol Red

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

How many hydrogen atoms will be present in the product?

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS1-5

During a chemical reaction, substances (called reactants) are combined to form new substances (called products). Which of the following accurately describes the reactants and the products of a chemical reaction?

• The products contain a different number of atoms than the reactants but have the same properties.

• The number of atoms and the properties are the same in the reactants and the products.

• The products contain the same number of atoms as the reactants but have different properties.

• The number of atoms and the properties are different in the reactants and the products.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Four students performed four different investigations by combining different substances. Their results are shown in the table to the left. In ​ ​ (a)   , a chemical reaction took place. The other experiments ​ (b)   result in a chemical reaction.

• Experiment 1

• Experiment 2

• Experiment 3

• Experiment 4

• did not

• did

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which observations are evidence that a chemical reaction took place?

Tags

NGSS.MS-PS1-2